JP4466325B2 - Turbocharger - Google Patents

Description

  The present invention relates to a turbocharger, and more particularly to a turbocharger in which a scroll in a turbine housing is partitioned by the turbine housing and a separate partition wall member.

  2. Description of the Related Art Conventionally, for example, a turbocharger having a configuration shown in FIG. The configuration of the turbocharger is known, but the overall configuration will be schematically described for easy understanding.

  The turbocharger 1 includes a center housing (bearing housing) 5 that rotatably supports a rotating shaft 3. A turbine impeller (turbine impeller) 7 is provided on one end side of the rotating shaft 3, and a compressor impeller (compressor impeller) 9 is provided on the other end side of the rotating shaft 3.

  A turbine housing 13 that covers the turbine impeller 7 is attached to a first flange 11 provided at one end of the center housing 5 by a plurality of attachments 15 such as attachment bolts. A compressor housing 19 that covers the compressor impeller 9 is attached to the second flange 17 provided on the other end side of the center housing 5 by a plurality of attachments 21.

  The turbine housing 13 is formed with a scroll 23 for introducing and accelerating exhaust gas from the engine and guiding it to the turbine impeller 7. The scroll 23 corresponds to the outer peripheral portion of the turbine impeller 7. An annular gas flow path 25 for supplying exhaust gas to the turbine impeller 7 is formed in the portion, and in this gas flow path 25, the exhaust gas supply direction to the blade portion of the turbine impeller 7 is formed. A shroud assembly 29 provided with a plurality of nozzle vanes 27 whose supply angle can be controlled is provided at equal intervals in the circumferential direction and is rotatable.

  The shroud assembly 29 includes an annular shroud 33 supported on the turbine housing 13 via a seal ring 31 and a nozzle support ring 35 provided opposite to the shroud 33 in the axial direction. The nozzle vane 27 is arranged between the shroud 33 and the nozzle support ring 35. A support shaft 37 provided integrally with the nozzle vane 27 is rotatably supported by the shroud 33 and the nozzle ring 35.

  A radially inner side of the nozzle support ring 35 is supported by a part of the center housing 5 via an annular heat shield member 39. At a position corresponding to the outer peripheral edge of the nozzle support ring 35, an inward flange-shaped annular partition wall portion 41 is formed integrally with the turbine housing 13 so as to protrude inward.

  Since the partition wall 41 is formed, an annular space 43 is partitioned from the scroll 23 between the partition wall 41, the nozzle support ring 35, and the first flange 11 of the center housing 5. Is formed. In order to prevent the exhaust gas from entering the space 43 from the clearance between the outer peripheral surface of the nozzle support ring 35 and the inner peripheral surface of the partition wall portion 41, the outer peripheral edge of the nozzle support ring 35 An annular seal member 45 is integrally attached to the outer peripheral edge (flange) 45F of the seal member 45 and is sandwiched between the first flange 11 and the turbine housing 13.

  With the above configuration, the exhaust gas in the scroll 23 can be prevented from directly contacting and contacting the seal member 45 and heated, and the exhaust gas can be prevented from entering the space 43. It is.

  A vane rotation mechanism 47 for rotating the nozzle vane 27 is provided in the space 43. More specifically, a ring member 49 is rotatably provided in the space 43, and a plurality of radial (radial) slits formed on the inner side of the ring member 49 include the above-described slits. The front end of a lever 51 whose base end is fixed to the support shaft 37 of the nozzle vane 27 is engaged.

  Further, a slit at an appropriate position of the ring member 49 is provided with a drive lever 57 provided integrally with one end of an operation shaft 55 rotatably supported by a part of the center housing 5 via a bush 53. The tip is engaged. An operating lever 59 provided integrally with the other end of the operating shaft 55 is linked to an operating rod 61 operated by an operating mechanism (not shown).

  The compressor housing 19 includes a suction port 63 that sucks air by the rotation of the compressor impeller 9 and a differential user 65.

  In the configuration as described above, when the exhaust gas of the engine is introduced into the scroll 23 of the turbine housing 13 from the introduction port (not shown), the exhaust gas is accelerated by gradually reducing the cross-sectional area of the scroll 23. And it is guide | induced to the nozzle vane 27, is supplied to the blade | wing part of the turbine impeller 7, rotates the turbine impeller 7, and exhaust gas is discharged | emitted from the exhaust port 13E.

  As described above, when the turbine impeller 7 is rotated, the compressor impeller 9 is rotated via the rotating shaft 3, and air is sucked from the suction port 63 and is supplied to the differential user 65 by the centrifugal force to become a high pressure.

There is Patent Document 1 as a prior example according to the present invention.
Japanese Patent Publication No. 7-13468

  In the conventional configuration as described above, in order to partition (partition) the scroll 23 and the space portion 43 in the turbine housing 13, an annular partition wall portion 41 is integrally formed inside the turbine housing 13. . Accordingly, the high temperature exhaust gas flowing in the scroll 23 is protected from directly contacting the seal member 45 provided so that the exhaust gas in the scroll 23 does not enter the space 43. Can be meaningful.

  However, the partition wall portion 41 is integrally formed when the turbine housing 13 is cast, and is formed with a relatively large thickness. Therefore, heat tends to be trapped, and during natural cooling after the engine is stopped, a large temperature gradient is generated between the outer surface of the turbine housing 13 and sometimes cracks are generated in the turbine housing 13 due to thermal stress.

  Further, as described above, since the partition wall portion 41 is configured to protrude inwardly inside the turbine housing 13, the configuration of the core for forming the scroll 23 is complicated, and the productivity of the turbine housing 13 is increased. In order to improve, further improvements have been demanded.

The present invention has been made in view of the conventional problems as described above, and includes a rotating shaft rotatably supported by a center housing, a turbine impeller provided at one end of the rotating shaft, and the rotating shaft. A turbocharger comprising a compressor impeller provided on an end side, a turbine housing covering the turbine impeller, and a compressor housing covering the compressor impeller, wherein the turbine housing is provided around the turbine impeller. A shroud assembly comprising a plurality of nozzle vanes capable of controlling the supply direction of exhaust gas to the turbine blades in an annular gas passage formed in a portion corresponding to the scroll formed on the outer periphery and the outer peripheral portion of the turbine blade. On the outer periphery of the nozzle support ring provided in the shroud assembly. In order to protect the seal member from exhaust gas flowing in the scroll, the flange of the annular seal member that is physically attached is provided between the flange of the center housing and the turbine housing. An annular partition member formed by a plate-like member is provided inside the turbine housing, and the annular flange portion provided in the partition member is overlapped with the flange of the seal member and the flange of the center housing. It is sandwiched between the turbine housing .

  In the turbocharger according to the present invention, the outer peripheral wall portion of the scroll is formed to have substantially the same thickness.

  According to the present invention, the turbine housing and the partition wall portion can be separately manufactured and combined, and the configuration of the core for forming the scroll of the turbine housing can be simplified. The thermal stress in the vicinity of the joint between the scroll and the partition wall can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Components having the same functions as those of the conventional components described above are denoted by the same reference numerals, and redundant description is omitted.

  Referring to FIG. 1, the overall configuration of the turbocharger 1 according to the embodiment of the present invention is substantially the same as the configuration of the conventional turbocharger described above, and therefore only the main part is shown and described. To do.

  The turbine housing 13 according to the present embodiment is attached to the first flange 11 in the center housing 5 via a plurality of attachments 15 in the same manner as the conventional turbine housing described above. And between this turbine housing 13 and the said 1st flange 11, the outer peripheral edge part of the sealing member 45 is clamped and fixed similarly to the conventional structure.

  In the turbine housing 13, in order to form the scroll 23, the inner surface of the outer peripheral wall portion 13 </ b> A surrounding the outer peripheral side of the scroll 23 is formed into a smooth curved surface without any uneven portion, and this outer periphery. The wall portion 13A is formed with substantially the same thickness throughout. Therefore, the structure of the core for forming the scroll 23 when casting the turbine housing 13 has a simpler shape, and the productivity of the turbine housing 13 can be improved.

  In order to protect the sealing member 45 from the high-temperature exhaust gas flowing in the scroll 23, a partition wall member 67 formed of a plate-like member is provided inside the turbine housing 13. The partition wall member 67 is made of a heat-resistant metal plate, and includes an annular trunk portion 67A disposed along the inner surface of the outer peripheral wall portion 13A of the turbine housing 13.

  And on the outer end side of the trunk portion 67A of the partition wall member 67, the flange 45F of the seal member 45 is overlapped between the first flange 11 and the turbine housing 13 in the center housing 5. And an annular outer flange portion 67B that is held in place. On the inner end side of the body 67A, an annular inner flange portion 67C having an inner peripheral edge close to the outer peripheral surface of the nozzle support ring 35 is provided.

  Therefore, the scroll 23 provided in the turbine housing 23 is a mode in which the turbine housing 23 and the inner flange portion 67C of the partition wall member 67 separate from the turbine housing 23 are formed.

  As understood from the above configuration, the seal member 45 for sealing the space 43 having the vane rotation mechanism 47 from the exhaust gas in the scroll 23 is provided between the seal member 45 and the scroll 23. The partition wall member 67 located at the position is protected so that the high-temperature exhaust gas flowing in the scroll 23 is not in direct contact.

  The turbine housing 13 and the partition wall member 67 are separate members, and are fixed by swaging the outer flange portion 67B between the end face of the turbine housing 13 and the first flange 11 in the center housing 5. Therefore, the partition wall member 67 can be easily attached to the turbine housing 13. Furthermore, since the turbine housing 13 and the partition wall member 67 are separate members, uneven portions on the inner peripheral surface of the outer peripheral wall portion 13A of the turbine housing 13 can be reduced, and thermal stress can be reduced.

  Furthermore, since the outer peripheral wall portion 13A of the turbine housing 13 has almost the same thickness throughout, the thermal stress can be reduced. The inner peripheral surface of the outer peripheral wall portion 13A is formed in a smooth curved surface over the scroll 23 portion, and the configuration of the core for forming the scroll 23 can be simplified. It is possible to improve the performance.

Further, since the partition wall member 67 is made of a plate-like member, the inner flange portion 67C can be formed in an appropriate curved surface, and the cut shape of the scroll 23 can be set to a desired shape.

It is a section explanatory view showing only the principal part of the turbocharger concerning the embodiment of the present invention. It is sectional explanatory drawing which showed the whole structure of the conventional turbocharger.

Explanation of symbols

3 ... Rotating shaft 5 ... Center housing (bearing housing)
7 ... Turbine impeller (turbine impeller)
9 ... Compressor impeller (compressor impeller)
DESCRIPTION OF SYMBOLS 11 ... 1st flange 13 ... Turbine housing 19 ... Compressor housing 23 ... Scroll 29 ... Shroud assembly 43 ... Space part 45 ... Seal member 47 ... Vane rotation mechanism 67 ... Partition wall member

Claims (2)

A rotating shaft rotatably supported by the center housing, a turbine impeller provided on one end side of the rotating shaft, a compressor impeller provided on the other end side of the rotating shaft, and a turbine covering the turbine impeller A turbocharger comprising a housing and a compressor housing that covers the compressor impeller, wherein the turbocharger is formed in a portion corresponding to a scroll formed in the turbine housing and an outer peripheral portion of the turbine impeller around the turbine impeller. A shroud assembly having a plurality of nozzle vanes capable of controlling the supply direction of the exhaust gas to the turbine blades is provided in the annular gas flow path, and is disposed on the outer periphery of the nozzle support ring provided in the shroud assembly. The flange of the annular seal member attached integrally is connected to the center. An annular partition provided between the flange of the housing and the turbine housing and formed by a plate-like member inside the turbine housing to protect the seal member from exhaust gas flowing in the scroll And an annular flange portion provided in the partition member is sandwiched between the flange of the center housing and the turbine housing in a state of being overlapped with the flange of the seal member. Turbocharger to do.   2. The turbocharger according to claim 1, wherein the outer peripheral wall portion of the scroll is formed to have substantially the same thickness.

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